HTML is nice and all but it's simply not a desirable option. Here are some things you can't do with HTML-based UI:
Render it behind non-HTML objects
Z-ordering, Z-elevation, mesh distortion, paste to canvas, use as a 3D face object, or any sort of "world-space" UI
Use native effects or blend modes
Use Construct objects like sprites/9-slice/etc.
See your results in the layout
In addition, you'll have to use CSS to make anything look nice. CSS is super powerful if you're a web designer trying to flex your skills. It's a pain for everyone else on the planet.
OP, this is the reality of Construct. Either learn html/css and cobble together a UI, or roll your own. I'd say that third-party plugins are kind of dead in the water right now (usable, but less reliable as time goes on), at least until someone picks up the torch. There is some progress happening in that department, from what I've seen in the community.
Honestly, Construct does soooo much already that it's probably going to be quicker for building a game than Unity (depending on the game). I hate building UI but I do it every time, and get quicker every time, often pulling in functions and assets from other projects.